基于FLAC3D的多层复杂采空区稳定性研究

Study of Stability of Multi-layer Complex Mined-out Areas based on FLAC3D

某矿山位于-360 m中段的金属矿开采已基本结束,遗留了大量复杂采空区,对周边矿体的开采和井下作业人员安全造成严重隐患。通过采空区精密探测和三维建模技术掌握采空区的三维形态和精确数据,利用FLAC3D有限差分法分析围岩的应力、位移和塑性区分布,结果表明:空区的大部应力集中在顶板中上部,数值模拟和力学分析表明空区顶板发生冒落的可能性是存在的,因此要尽量减少对大空区的扰动,合理布置采场跨度,优化采场参数,同时注重空区角隅处的拉应力及大位移量的变化,减少采空区周边采矿和爆破对空区振动的影响,并且及时对空区进行充填。

The metal mining of a certain mine located in the level of-360 has been basically completed,leaving behind a large number of complex mined-out areas that pose serious risks to the mining of surrounding ore bodies and the safety of underground workers.Through precise detection of mined-out areas and three-dimensional modeling technology,the three-dimensional morphology and precise data of mined-out areas are mastered.FLAC 3D finite difference method is used to analyze the distribution of stress,displacement and plastic zone of surrounding rocks.The results show that most of the stress in the mined-out areas is concentrated in the upper middle part of the roof.Numerical simulation and mechanical analysis show that there is a possibility of roof collapse in the mined-out areas.Therefore,it is necessary to minimize disturbance to the large mined-out areas,reasonably arrange the span of the mining area and optimize the parameters of the mining area.And meanwhile attention should be paid to the changes in tensile stress and large displacement at the corners of the mined-out areas,so as to reduce the vibration impact of mining and blasting around the mined-out areas on the mined-out areas,and the mined-out areas should be filled in a timely manner.